Measurement of branching fractions and search for CP violation in $D^0 → π^+π^-η, D^0 → K^+K^-η$, and $D^0 → Φη$ at Belle

Journal Article · Mon Sep 13 00:00:00 EDT 2021 · Journal of High Energy Physics (Online)

DOI:https://doi.org/10.1007/jhep09(2021)075· OSTI ID:1823610

Li, L. K.; Schwartz, A. J.; Kinoshita, K.; Adachi, I.; Aihara, H.; Al Said, S.; Asner, D. M.; Atmacan, H.; Aulchenko, V.; Aushev, T.; Ayad, R.; Babu, V.; Bahinipati, S.; Behera, P.; Bennett, J.; Bessner, M.; Bilka, T.; Biswal, J.; Bobrov, A.; Bonvicini, G. ; Bozek, A.; Bračko, M.; Branchini, P.; Browder, T. E.; Budano, A.; Campajola, M.; Červenkov, D.; Chang, M. -C.; Chang, P.; Chekelian, V.; Chen, A.; Chen, Y. Q.; Cheon, B. G.; Chilikin, K.; Cho, H. E.; Cho, K.; Cho, S. -J.; Choi, S. -K.; Choi, Y.; Choudhury, S.; Cinabro, D.; Cunliffe, S.; Das, S.; Dash, N.; De Nardo, G.; De Pietro, G.; Dhamija, R.; Di Capua, F.; Doležal, Z.; Dong, T. V.; Eidelman, S.; Epifanov, D.; Ferber, T.; Fulsom, B. G.; Garg, R.; Gaur, V.; Giri, A.; Goldenzweig, P.; Golob, B.; Graziani, E.; Gu, T.; Guan, Y.; Hadjivasiliou, C.; Halder, S.; Hayasaka, K.; Hou, W. -S.; Inami, K.; Ishikawa, A.; Iwasaki, M.; Iwasaki, Y.; Jacobs, W. W.; Jang, E. -J.; Jia, S.; Jin, Y.; Joo, K. K.; Kang, K. H.; Karyan, G.; Kiesling, C.; Kim, C. H.; Kim, D. Y.; Kim, K. -H.; Kim, S. H.; Kim, Y. -K.; Kodyš, P.; Konno, T.; Korobov, A.; Korpar, S.; Kovalenko, E.; Križan, P.; Kroeger, R.; Krokovny, P.; Kuhr, T.; Kumar, M.; Kumara, K.; Kuzmin, A.; Kwon, Y. -J.; Lalwani, K.; Laurenza, M.; Lee, S. C.; Li, C. H.; Gioi, L. Li; Libby, J.; Lieret, K.; Liventsev, D.; Masuda, M.; Matvienko, D.; Merola, M.; Metzner, F.; Miyabayashi, K.; Mizuk, R.; Mohanty, G. B.; Mori, T.; Nakao, M.; Natkaniec, Z.; Natochii, A.; Nayak, L.; Nayak, M.; Niiyama, M.; Nisar, N. K.; Nishida, S.; Nishimura, K.; Ono, H.; Oskin, P.; Pakhlov, P.; Pakhlova, G.; Pardi, S.; Park, S. -H.; Passeri, A.; Paul, S.; Pedlar, T. K.; Pestotnik, R.; Piilonen, L. E.; Podobnik, T.; Popov, V.; Prencipe, E.; Prim, M. T.; Rout, N.; Russo, G.; Sahoo, D.; Sakai, Y.; Sandilya, S.; Sangal, A.; Santelj, L.; Sanuki, T.; Savinov, V.; Schnell, G.; Schwanda, C.; Seino, Y.; Senyo, K.; Shapkin, M.; Sharma, C.; Shen, C. P.; Shiu, J. -G.; Shwartz, B.; Sokolov, A.; Solovieva, E.; Starič, M.; Stottler, Z. S.; Sumihama, M.; Sumiyoshi, T.; Takizawa, M.; Tanida, K.; Tenchini, F.; Uchida, M.; Uglov, T.; Unno, Y.; Uno, K.; Uno, S.; Vahsen, S. E.; Van Tonder, R.; Varner, G.; Vinokurova, A.; Waheed, E.; Wang, C. H.; Wang, M. -Z.; Wang, P.; Wang, X. L.; Watanuki, S.; Won, E.; Yabsley, B. D.; Yan, W. B.; Yang, S. B.; Ye, H.; Yelton, J.; Yin, J. H.; Yusa, Y.; Zhang, Z. P.; Zhilich, V.; Zhukova, V.

We measure the branching fractions and CP asymmetries for the singly Cabibbo-suppressed decays $D^0 → π^+π^-η, D^0 → K^+K^-η$, and $D^0 → Φη$, using 980 fb^-1 of data from the Belle experiment at the KEKB e⁺e^- collider. We obtain $$$$\mathcal{B}(D^0 → π^+π^-η = \mathrm{[1.22 ± 0.02 (stat) ± 0.02(syst) ± 0.03}(\mathcal{B}_{\mathrm{ref}})] \mathrm{x 10^{-3}}$$$$ $$$$\mathcal{B}(D^0 → K^+K^-η = \mathrm{[1.80^{+0.07}_{-0.06}(stat) ± 0.04 (syst) ± 0.05}(\mathcal{B}_{\mathrm{ref}})] \mathrm{x 10^{-4}}$$$$ $$$$\mathcal{B}(D^0 → Φη = \mathrm{[1.84 ± 0.09 (stat) ± 0.0 (syst) ± 0.05}(\mathcal{B}_{\mathrm{ref}})] \mathrm{x 10^{-4}}$$$$ where the third uncertainty ($$\mathcal{B}_{\mathrm{ref}}$$) is from the uncertainty in the branching fraction of the reference mode $D^0 → K^-π^+η$. The color-suppressed decay $D^0 → Φη$ is observed for the first time, with very high significance. The results for the CP asymmetries are $$$$A_{CP} (D^0 → π^+π^-η) = \mathrm{[0.9 ± 1.2 (stat) ± 0.5 (syst)]}\%$$$$ $$$$A_{CP} (D^0 → K^+K^-η) = \mathrm{[-1.4 ± 3.3 (stat) ± 1.1 (syst)]}\%$$$$ $$$$A_{CP} (D^0 → Φη) = \mathrm{[-1.9 ± 4.4 (stat) ± 0.6 (syst)]}\%$$$$ The results for $D^0 → π^+π^-η$ are a significant improvement over previous results. The branching fraction and A_CP results for $D^0 → K^+K^-η$, and the ACP result for $D^0 → Φη$, are the first such measurements. No evidence for CP violation is found in any of these decays.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States)
• Sponsoring Organization: National Science Foundation (NSF); USDOE Office of Science (SC), High Energy Physics (HEP)
• Contributing Organization: BELLE Collaboration
• Grant/Contract Number: SC0012704
• OSTI ID: 1823610
• Report Number(s): BNL--222212-2021-JAAM
• Journal Information: Journal of High Energy Physics (Online), Journal Name: Journal of High Energy Physics (Online) Journal Issue: 9 Vol. 2021; ISSN 1029-8479
• Publisher: Springer Nature
• Country of Publication: United States
• Language: English

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